實現步驟：
1、獲取ConnectivityManager對象
Context context = activity.getApplicationContext();
// 獲取手機所有連接管理對象（包括對wi-fi,net等連接的管理）
ConnectivityManager connectivityManager = (ConnectivityManager)context.getSystemService(Context.CONNECTIVITY_SERVICE);

2、獲取NetworkInfo對象
// 獲取NetworkInfo對象
NetworkInfo[] networkInfo = connectivityManager.getAllNetworkInfo();

3、判斷當前網絡狀態是否為連接狀態
if (networkInfo[i].getState() == NetworkInfo.State.CONNECTED)
{
return true;
}

4、在AndroidManifest.xml中添加訪問當前網絡狀態權限
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"></uses-permission>

代碼如下：

public class ClassTestDemoActivity extends Activity
{
@Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
if (isNetworkAvailable(ClassTestDemoActivity.this))
{
Toast.makeText(getApplicationContext(), "當前有可用網絡！", Toast.LENGTH_LONG).show();
}
else
{
Toast.makeText(getApplicationContext(), "當前沒有可用網絡！", Toast.LENGTH_LONG).show();
}
}

/**
* 檢查當前網絡是否可用
*
* @param context
* @return
*/

public boolean isNetworkAvailable(Activity activity)
{
Context context = activity.getApplicationContext();
// 獲取手機所有連接管理對象（包括對wi-fi,net等連接的管理）
ConnectivityManager connectivityManager = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);

if (connectivityManager == null)
{
return false;
}
else
{
// 獲取NetworkInfo對象
NetworkInfo[] networkInfo = connectivityManager.getAllNetworkInfo();

if (networkInfo != null && networkInfo.length > 0)
{
for (int i = 0; i < networkInfo.length; i++)
{
System.out.println(i + "===狀態===" + networkInfo[i].getState());
System.out.println(i + "===類型===" + networkInfo[i].getTypeName());
// 判斷當前網絡狀態是否為連接狀態
if (networkInfo[i].getState() == NetworkInfo.State.CONNECTED)
{
return true;
}
}
}
}
return false;
}
}

ConnectivityManager cm = (ConnectivityManager) ctx
.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo netInfo = cm.getActiveNetworkInfo();
if (netInfo != null && netInfo.isConnectedOrConnecting()) {
// 有可用的網絡
}

0android判斷網絡是否連接

從程序開發的角度來開發該功能如下代碼及代碼中的注釋即可理解：ConnectivityManager manager = (ConnectivityManager) getSystemService(CONNECTIVITY_SERVICE); // 檢查網絡連接，如果無網絡可用，就不需要進行連網操作等 NetworkInfo info = manager.getActiveNetworkInfo(); if (info == null || !manager.getBackgroundDataSetting()) { return "無網絡鏈接"; } return "網絡暢通";